Where the worm dies not, and the fire is not quenched.
All Commentaries on Mark 9:48 Go To Mark 9
Gregory of Nyssa
AD 394
Nor, too, does anything which afflicts the senses here equal in torment the future life of sinners. Even if we denote some of those torments by terms familiar to us here, the difference is not slight. When you hear the word “fire,” you have been taught to think of it differently from ordinary fire, since a new factor is added. For that fire is not quenched, while experience has devised many ways to quench the fire we know. And there is a great difference between fire which is quenched and that which cannot be put out. They are, therefore, different, and not the same. Then again, when a person hears the word “worm,” the analogy must not be misapplied directly from the creature we know to the eternal. For the addition of the phrase “that does not die” suggests the thought that this worm is not simply the creature we know.